/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * This library is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU Lesser General Public License as published by 
 * the Free Software Foundation; either version 2.1 of the License, or 
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License 
 * along with this library; if not, write to the Free Software Foundation, 
 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 *
 * ------------------------
 * PeriodAxisLabelInfo.java
 * ------------------------
 * (C) Copyright 2004, 2005, by Object Refinery Limited and Contributors.
 *
 * Original Author:  David Gilbert (for Object Refinery Limited);
 * Contributor(s):   -;
 *
 * $Id: PeriodAxisLabelInfo.java,v 1.6 2005/05/20 09:16:30 mungady Exp $
 *
 * Changes
 * -------
 * 01-Jun-2004 : Version 1 (DG);
 * 23-Feb-2005 : Replaced Spacer with RectangleInsets (DG);
 * 01-Mar-2005 : Modified constructors to accept DateFormat (DG);
 * 20-May-2005 : Added default constants and null argument checks in the 
 *               constructor (DG);
 * 
 */

package org.jfree.chart.axis;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.Paint;
import java.awt.Stroke;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.text.DateFormat;
import java.util.Date;
import java.util.TimeZone;

import org.jfree.data.time.RegularTimePeriod;
import org.jfree.io.SerialUtilities;
import org.jfree.ui.RectangleInsets;

/**
 * A record that contains information for one "band" of date labels in 
 * a {@link PeriodAxis}.
 */
public class PeriodAxisLabelInfo implements Cloneable, Serializable {
    
    // TODO: this class is mostly immutable, so implementing Cloneable isn't
    // really necessary.  But there is still a hole in that you can get the
    // dateFormat and modify it.  We could return a copy, but that would slow
    // things down. Needs resolving.
    
    /** For serialization. */
    private static final long serialVersionUID = 5710451740920277357L;
    
    /** The default insets. */
    public static final RectangleInsets DEFAULT_INSETS 
        = new RectangleInsets(2, 2, 2, 2);
    
    /** The default font. */
    public static final Font DEFAULT_FONT 
        = new Font("SansSerif", Font.PLAIN, 10);
    
    /** The default label paint. */
    public static final Paint DEFAULT_LABEL_PAINT = Color.black;
    
    /** The default divider stroke. */
    public static final Stroke DEFAULT_DIVIDER_STROKE = new BasicStroke(0.5f);
    
    /** The default divider paint. */
    public static final Paint DEFAULT_DIVIDER_PAINT = Color.gray;

    /** The subclass of {@link RegularTimePeriod} to use for this band. */
    private Class periodClass;
    
    /** Controls the gaps around the band. */
    private RectangleInsets padding;
    
    /** The date formatter. */
    private DateFormat dateFormat;
    
    /** The label font. */
    private Font labelFont;
    
    /** The label paint. */
    private transient Paint labelPaint;
    
    /** A flag that controls whether or not dividers are visible. */
    private boolean drawDividers;
    
    /** The stroke used to draw the dividers. */
    private transient Stroke dividerStroke;
    
    /** The paint used to draw the dividers. */
    private transient Paint dividerPaint;
        
    /**
     * Creates a new instance.
     * 
     * @param periodClass  the subclass of {@link RegularTimePeriod} to use 
     *                     (<code>null</code> not permitted).
     * @param dateFormat  the date format (<code>null</code> not permitted).
     */
    public PeriodAxisLabelInfo(Class periodClass, DateFormat dateFormat) {
        this(
            periodClass, dateFormat, DEFAULT_INSETS, DEFAULT_FONT, 
            DEFAULT_LABEL_PAINT, true, DEFAULT_DIVIDER_STROKE, 
            DEFAULT_DIVIDER_PAINT
        );
    }
    
    /**
     * Creates a new instance.
     * 
     * @param periodClass  the subclass of {@link RegularTimePeriod} to use
     *                     (<code>null</code> not permitted).
     * @param dateFormat  the date format (<code>null</code> not permitted).
     * @param padding  controls the space around the band (<code>null</code> 
     *                 not permitted).
     * @param labelFont  the label font (<code>null</code> not permitted).
     * @param labelPaint  the label paint (<code>null</code> not permitted).
     * @param drawDividers  a flag that controls whether dividers are drawn.
     * @param dividerStroke  the stroke used to draw the dividers 
     *                       (<code>null</code> not permitted).
     * @param dividerPaint  the paint used to draw the dividers 
     *                      (<code>null</code> not permitted).
     */
    public PeriodAxisLabelInfo(Class periodClass, DateFormat dateFormat, 
                               RectangleInsets padding,
                               Font labelFont, Paint labelPaint, 
                               boolean drawDividers, Stroke dividerStroke, 
                               Paint dividerPaint) {
        if (periodClass == null) {
            throw new IllegalArgumentException("Null 'periodClass' argument.");   
        }
        if (dateFormat == null) {
            throw new IllegalArgumentException("Null 'dateFormat' argument.");   
        }
        if (padding == null) {
            throw new IllegalArgumentException("Null 'padding' argument.");   
        }
        if (labelFont == null) {
            throw new IllegalArgumentException("Null 'labelFont' argument.");   
        }
        if (labelPaint == null) {
            throw new IllegalArgumentException("Null 'labelPaint' argument.");   
        }
        if (dividerStroke == null) {
            throw new IllegalArgumentException("Null 'dividerStroke' argument.");   
        }
        if (dividerPaint == null) {
            throw new IllegalArgumentException("Null 'dividerPaint' argument.");   
        }
        this.periodClass = periodClass;
        this.dateFormat = dateFormat;
        this.padding = padding;
        this.labelFont = labelFont;
        this.labelPaint = labelPaint;
        this.drawDividers = drawDividers;
        this.dividerStroke = dividerStroke;
        this.dividerPaint = dividerPaint;
    }
    
    /**
     * Returns the subclass of {@link RegularTimePeriod} that should be used 
     * to generate the date labels.
     * 
     * @return The class.
     */
    public Class getPeriodClass() {
        return this.periodClass;   
    }
    
    /**
     * Returns the date formatter.
     * 
     * @return The date formatter (never <code>null</code>).
     */
    public DateFormat getDateFormat() {
        return this.dateFormat;   
    }
    
    /**
     * Returns the padding for the band.
     * 
     * @return The padding.
     */
    public RectangleInsets getPadding() {
        return this.padding;   
    }
    
    /**
     * Returns the label font.
     * 
     * @return The label font (never <code>null</code>).
     */
    public Font getLabelFont() {
        return this.labelFont;   
    }
    
    /**
     * Returns the label paint.
     * 
     * @return The label paint.
     */
    public Paint getLabelPaint() {
        return this.labelPaint;   
    }
    
    /**
     * Returns a flag that controls whether or not dividers are drawn.
     * 
     * @return A flag.
     */
    public boolean getDrawDividers() {
        return this.drawDividers;   
    }
    
    /**
     * Returns the stroke used to draw the dividers.
     * 
     * @return The stroke.
     */
    public Stroke getDividerStroke() {
        return this.dividerStroke;   
    }
    
    /**
     * Returns the paint used to draw the dividers.
     * 
     * @return The paint.
     */
    public Paint getDividerPaint() {
        return this.dividerPaint;   
    }
    
    /**
     * Creates a time period that includes the specified millisecond, assuming
     * the given time zone.
     * 
     * @param millisecond  the time.
     * @param zone  the time zone.
     * 
     * @return The time period.
     */
    public RegularTimePeriod createInstance(Date millisecond, TimeZone zone) {
        RegularTimePeriod result = null;
        try {
            Constructor c = this.periodClass.getDeclaredConstructor(
                new Class[] {Date.class, TimeZone.class}
            );
            result = (RegularTimePeriod) c.newInstance(
                new Object[] {millisecond, zone}
            );   
        }
        catch (Exception e) {
            // do nothing            
        }
        return result;  
    }

    /**
     * Tests this object for equality with an arbitrary object.
     * 
     * @param obj  the object to test against (<code>null</code> permitted).
     * 
     * @return A boolean.
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;   
        }
        if (obj instanceof PeriodAxisLabelInfo) {
            PeriodAxisLabelInfo info = (PeriodAxisLabelInfo) obj;
            if (!info.periodClass.equals(this.periodClass)) {
                return false;   
            }
            if (!info.dateFormat.equals(this.dateFormat)) {
                return false;   
            }
            if (!info.padding.equals(this.padding)) {
                return false;   
            }
            if (!info.labelFont.equals(this.labelFont)) {
                return false;
            }
            if (!info.labelPaint.equals(this.labelPaint)) {
                return false;   
            }
            if (info.drawDividers != this.drawDividers) {
                return false;   
            }
            if (!info.dividerStroke.equals(this.dividerStroke)) {
                return false;   
            }
            if (!info.dividerPaint.equals(this.dividerPaint)) {
                return false;   
            }
            return true;
        }
        return false;
    }
    
    /**
     * Returns a hash code for this object.
     * 
     * @return A hash code.
     */
    public int hashCode() {
        int result = 41;
        result = 37 * this.periodClass.hashCode();
        result = 37 * this.dateFormat.hashCode();
        return result;
    }
    
    /**
     * Returns a clone of the object.
     * 
     * @return A clone.
     * 
     * @throws CloneNotSupportedException if cloning is not supported.
     */
    public Object clone() throws CloneNotSupportedException {
        Object clone = (PeriodAxisLabelInfo) super.clone();
        return clone;
    }
    
    /**
     * Provides serialization support.
     *
     * @param stream  the output stream.
     *
     * @throws IOException  if there is an I/O error.
     */
    private void writeObject(ObjectOutputStream stream) throws IOException {
        stream.defaultWriteObject();
        SerialUtilities.writePaint(this.labelPaint, stream);
        SerialUtilities.writeStroke(this.dividerStroke, stream);
        SerialUtilities.writePaint(this.dividerPaint, stream);
    }

    /**
     * Provides serialization support.
     *
     * @param stream  the input stream.
     *
     * @throws IOException  if there is an I/O error.
     * @throws ClassNotFoundException  if there is a classpath problem.
     */
    private void readObject(ObjectInputStream stream) 
        throws IOException, ClassNotFoundException {
        stream.defaultReadObject();
        this.labelPaint = SerialUtilities.readPaint(stream);
        this.dividerStroke = SerialUtilities.readStroke(stream);
        this.dividerPaint = SerialUtilities.readPaint(stream);
    }
   
}
